devel/rudeconfig: Fix build with Clang 6

src/Base64Encoder.cpp:170:25: error: cast from pointer to smaller type 'char' loses information

retval[outlength]=(char) NULL;
                  ^~~~~~~~~~~

http://beefy12.nyi.freebsd.org/data/head-amd64-default/p479076_s338486/logs/errors/rudeconfig-5.0.5_2.log

• Make sure all files use Unix line endings

PR: 230920
Submitted by: tobik
Approved by: lowmaster@web.de (maintainer timeout, 2 weeks)